Influence of age on the quality of immature canine oocyte
Keywords:
Age, Canine oocyte, Brillant cresyl blueAbstract
Among some factors that influence the quality of canine oocytes, age is well studied. Knowing that the morphological assessment of oocytes is a useful tool for this analysis, the use of new techniques such as the brilliant cresyl blue staining (BCB) increases this assessment. The objective of this work was to analyze the quantity and the oocyte quality of bitches in different age groups through the conventional morphological evaluation, in addition to the bright cresyl blue dye. For this purpose, 2.302 oocytes from 33 bitches were divided into four age groups from 1 to 3 years old; 4-6, 7-10 and over 10 years old and their oocytes were classified as G1, G2 and G3, as well as stained (BCB (+)) and non-stained (BCB (-)). The values were compared using the Kruskal test -Wallis and Dunn post-test, by which it was possible to obtain higher amounts of G1 and BCB (+) oocytes in the range of 1 to 3 years, indicating that this range oocytes have a greater chance of success in fertilization processes and in vitro production, for example.
References
ARMSTRONG, D.T. Effects of maternal age on oocyte developmental competence. Theriogenology, v.55, p.1303–1322, 2001.
HEWITT, D.A.; ENGLAND, G.C.W. The effect of oocyte size and bitch age upon oocyte nuclear maturation in vitro. Theriogenology, v.49, n.5, p.957-966. 1998.
JEWGENOW, K.; FERNANDEZ-GONZALEZ, L.; JÄNSCH, S.; VIERTEL, D.; ZAHMEL, J. Brilliant cresyl blue staining allows the selection for developmentally competent immature feline oocytes. Theriogenology, v.126, p.320–325. 2019.
KARAMISHABANKAREH, H.; MIRSHAMSI, S.M.; Selection of developmentally competent sheep zygotes using the Brilliant Cresyl Blue (ACB) test after IVF. Small Ruminant Research, v.105, n.1, 250-254. 2012.
LOPES, G.; SOUSA, M.; LUVONI, G.C.; ROCHA, A. Recovery rate, morphological quality and nuclear maturity of canine cumulus-oocyte complexes collected from anestrous or diestrous bitches of different ages. Theriogenology, v.68, p.821-825, 2007.
NICKSON, D.A.; BOYD, J.S.; ECKERSALL, P.D.; FERGUSON, J.M.; HARVEY, M.J.; RENTON, J.P. Molecular biology methods for monitoring oocyte and in vitro fertilization in bitches. Journal of Reproduction and Fertility, v.47, p231-240, 1993.
ROCHA, A.A.; BASTOS, R.; CUNHA, I.C.N.; QUIRINO, C.R. Maturação in vitro de oócitos de cadelas domésticas: efeitos na qualidade oocitária e presença espermática na maturação in vitro. Revista Portuguesa de Ciências Veterinárias, v.102, p.267-284, 2007.
